This project will test the on-farm feasibility of automated headgates as a means of regulating and measuring the flow of irrigation water to farmer fields.
Producer George Davis began in 1999 to assess the modifications needed to automate the headgate, and Brian Sauer, water conservation specialist with the Bureau of Reclamation, designed the installation. The automated headgate project was completed in the summer of 2000 and evaluated at the end of the 2000 irrigation season and through the 2001 season.
Despite minor programming glitches in the controller, the automated headgate has functioned reliably, opening and closing depending on the fluctuating water level in the delivery lateral. The system provided a constant flow to the field, without producer intervention, eliminating time typically spent on observation and manual adjustment. The amount of water delivered to the headgate was reduced to the amount needed, as opposed to the excess volumes delivered in the past to assure adequate delivery.
The project sought to evaluate how accurately the automated headgate device delivered a specific amount of irrigation water, the headgate’s dependability and the amount of time it saved the farmer. The project also assessed the economic benefits of reducing excess water fees and flooding problems that have been caused by fluctuating water levels.
The accuracy of this headgate alleviated the need for 2.5-acre feet of water during the 2001 season. That’s based on measured reductions of 9 miner’s inches of irrigation water for seven 24-hour irrigations.
In addition, the producer estimated that he saved 30 hours during the season by not having to repeatedly check water delivery. Those savings in time should increase as the dependability of the system is proved.
The system, developed by the Bureau of Reclamation and estimated to cost between $1,500 and $2,300, includes a water-level sensor, a gate actuator, solar panel, 12-volt battery and necessary electronic components. All of the components can be purchased “off the shelf” and are easily purchased and assembled.
During testing, the gate not only functioned as hoped (with a few minor calibration difficulties rectified early in the season), but its components worked in the intense heat, humidity and dust. In addition, farmers who have used the headgate control system appear to be comfortable with its operation.
The project team says that extrapolating results from this project to hundreds of diversion points on thousands of acres in the Treasure Valley of Idaho, and in other irrigated areas, could mean a huge saving in waste water often spilled for thorough irrigation. That would reduce associated charges to producers, especially in short water years. The system could also save the time farmers spend opening and closing diversion gates and improve water quality on the Boise River.
“Increasing the efficiency of water use will directly affect the total maximum daily load allocations mandated by the U.S. courts and the Environmental Protection Agency by reducing agricultural runoff, thus sustaining irrigated agriculture,” the project team says.
One automated headgate alleviated the need for around 2.5 acre-feet of water and saved the producer about 30 hours. The project team extrapolated those benefits to the 300,000 acres irrigated by canal and lateral water-delivery systems in the Treasure Valley of Idaho (Ada and Canyon counties). A typical headgate serves 150 acres, meaning roughly 2,000 headgates in the valley. That would mean a reduction of about 5,000 acre-feet of water diverted from local streams. At $20 an acre-foot, the 5,000 acre-feet saved comes to $100,000 per season. Producers, meanwhile, would save 60,000 hours per season, time previously spent checking headgates that could be devoted to other endeavors.
In addition to savings in water and time, avoiding the diversion of 5,000 acre-feet of water means less chance the water will become degraded by sediment, nutrients or raised temperatures before it becomes return flow to the local streams. That will improve the quality of the water for fish and wildlife.
FARMER ADOPTION AND DIRECT IMPACT
Progressive producers and irrigation districts in the area have been assessing the automated headgates for installation on their own canals and laterals. In addition, interest in the headgates has prompted funding sources other than Western SARE to provide for installation of four more headgates located around the valley. A company has developed a control box being tested on two sites that will provide all the electronics needed to operate the system. And irrigation districts have expressed interest in coupling the automated headgates with canal gates operated by the Bureau of Reclamation.
FUTURE RECOMMENDATIONS OR NEW HYPOTHESES
The final reports suggests that while the producer in a Sustainable Agriculture Research and Education grant is they key participant and should remain the lead in the project application, the SARE-funded projects need more than just the producer to handle the correspondence and keep the records. With this project, the technical advisor from the Bureau of Reclamation, with assistance from the Southwest Idaho RC&D, were integral. The recommendation is that an administrative assistant be accommodated in future grants to help the technical advisor with the paperwork.
DISSEMINATION OF FINDINGS
The project was visited during a field day conducted by the Canyon Soil Conservation District and attended by 25 producers. In addition, many individuals visited the project. Although not funded by the SARE grant, copies of presentations given by Bureau of Reclamation technical representatives have been provided to at least 500 people.
REACTIONS FROM FARMERS AND RANCHERS
Some farmers like the idea of automatic measures of their water flow, while others are skeptical.
Among the comments the project team received from farmers are these:
“I don’t want my water measured.”
“I have always had plenty of water and I don’t want less.”
“Maybe this will keep people from taking my water before it gets to my farm.”
“This will make sure I get the water I order and give me a record.”
“There will be a more constant flow in the delivery through automation.”
“How reliable and accurate is this system?”
“Can I go back to manual operation easily?”
The most positive comment was the realization that farmers would consistently get the water they need, at the same time keeping them within their allotments and reducing the need to buy more water at higher rates.